<template>
  <el-menu default-active="1-4-1" class="el-menu-vertical-demo" @open="handleOpen" @close="handleClose" :collapse="isCollapse" background-color="#545c64" text-color="#fff" active-text-color="#ffd04b">
    <h3>{{ isCollapse ? '后台' : '后台管理系统' }}</h3>
    <el-menu-item @click="clickMenu(item)" v-for="item in nochilder" :key="item.name" :index="item.name">
      <i :class="`el-icon-${item.icon }`"></i>
      <span slot="title">{{item.label}}</span>
    </el-menu-item>
    <!-- index和key一样代表着唯一性 -->
    <el-submenu :index="item.label" v-for="item in haschildren" :key="item.label">
      <template slot="title">
        <i :class="`el-icon-${item.icon}`"></i>
        <span slot="title">{{item.label}}</span>
      </template>
      <el-menu-item-group  v-for="item2 in item.children" :key="item2.name">
        <el-menu-item @click="clickMenu(item2)" :index="item2.name">{{ item2.label }}</el-menu-item>
      </el-menu-item-group>
    </el-submenu>
  </el-menu>
</template>
<script>
import Cookie from "js-cookie"
export default {
  data() {
    return {
    }
  },
  methods: {
    handleOpen(key, keyPath) {
      console.log(key, keyPath)
    },
    handleClose(key, keyPath) {
      console.log(key, keyPath)
    },
    //点击菜单
    clickMenu(item) {
      // 当前路由与跳转路由不一致才允许跳转
      //$route表示当前路由，$router表示要跳转的路由
      if(this.$route.path !== item.path && !(this.$route.path === '/home' && (item.path === '/'))){
        this.$router.push(item.path)
      }
      this.$store.commit('selectMenu', item)
     
    }
  },
  computed: {
    // 没有子菜单
    nochilder() {
      return this.menuData.filter(item => !item.children)
    },
    //有子菜单
    haschildren() {
      return this.menuData.filter(item => item.children)
    },
    menuData(){
      //判断当前数据，如果缓存中没有，则当前store中去获取
     return JSON.parse(Cookie.get('menu')) || this.$store.state.tab.menu
    },
    //用于控制菜单的展开还是收起
    isCollapse(){
       return this.$store.state.tab.isCollapse
    }
  }
}
</script>
<style lang="less" scoped>
.el-menu-vertical-demo:not(.el-menu--collapse) {
  width: 200px;
  min-height: 400px;
}
.el-menu {
  height: 100vh;
  border-right: none;
  h3 {
    line-height: 48px;
    text-align: center;
    color: white;
    font-weight: 400;
    font-size: 16px;
  
  }
}
</style>